Evaluation of Drought Donors at Reproductive Stage in Rice
2. Materials and Method
Seventy five land races / germplasm lines including check varieties were grown in dry
season, 2012 in alpha lattice with two replications to evaluate reproductive stage
drought donors amongst the materials. Adequate drought stress was applied at
reproductive stage to screen the materials on the basis of various parameters. Amongst
these 75 genotypes best donor is identified. Five representative plants for each
genotype in each replication were randomly selected to record observations on plant
height (cm), total tillers per plant, panicle length, grains per panicle, spikelet fertility
and per se yield. Days to 50% flowering were computed on plot basis. Seed weight (g)
was recorded by weighing 100 grains of each cultivar. The mean data after computing
for each character was subjected to standard methods of analyses of variance.
Rice genotypes showed considerable differences in grain yield and varied from 0.16 t
ha-1 (RTS 4) to 1.32 t ha-1 (UPLRI 4). In present study, results indicated that UPLRI 4
recorded highest grain yield(1.32 t ha-1 ) along with good tiller number. But, the
genotype has 59% spikelet sterility and poor harvest index. one another genotype
Taichung 65(0.84 t ha-1) was as good yielder under reproductive stage drought stress
condition. Further, rice genotypes showed a wide variation in yield components such
as ear bearing tiller hill-1 (EBT) and harvest index (HI). A high number of productive
tillers have been considered a crucial diagnosis index along with a high spikelet m-2
resulting in a higher yield of tillering cereal crops. IR 1561-228-3-3 and RD21 were
good performer in case of tiller number(13.5) and (12.5) respectively under stress.
TKM 6 showed highest total dry matter production (92.31 gram) followed by BPI RI
10 (89.79 gram) and Dinorado (85.97 gram). Taichung 65 is having next best genotype
with respect to yield. But, the genotypes exhibit less spikelet sterility, more harvest
index and tiller number as compared to UPLRI 4.The third donor for drought is
Kinastano with some yield under drought.
4. Conclusion
Drought intensity may vary from place to place, depending on soil type and amount
and intensity of rainfall. Therefore varietal response to drought is diverse. UPLRI 4
was identified best donor among these genotypes on the basis of highest grain yield
along with good tiller number. Consequently, the search for new donors should be
continued to improve drought tolerance under target environment.